A Fragile Watermarking Algorithm for Strict Image Authentication in the Wavelet Domain

A fragile watermarking algorithm which is based on watermark scrambling in the wavelet domain is discussed in this paper. In the proposed algorithm, chaotic signals are generated using logistic mapping and are used for scrambling the original watermark. The initial values of logistic mapping are taken as private keys. The host image is decomposed into four bands using integer wavelet transform; and the scrambled watermark is embedded in the low frequency band. Any modification made to the original image is reflected in the watermark.